Hi Adam,
Yes, I just saw that and I put it in and it has stopped the & from changing to & But still the charts are not showing.
For the project I am doing I have an extra button to show a preview (including uploaded css/images/templates) and the chart now shows fine (I generate a html page which is shown inside a iframe), so it is only in the cute editor that it does not show.
I am trying to get it on a live server, if you want to check it out.